Are bubbles in ice the potential space for hydrogen storage?

Abstract

A major challenge in hydrogen storage is to achieve higher storage capacity, simpler storage technology, less capital cost, lower storage risk, and near zero-carbon emissions. Here, we suggested that bubbles formed in the ice provide the potential space for hydrogen storage as needs. Further, we proposed a coupled mechanism of the supercooled pre-melted quasi-liquid layer to thermoelectric force under a temperature gradient for explaining the bubble formation in ice, based on both diverse laboratory experiments from the firn specimens at different stresses and temperatures and related assumption of thermoelectric effect. As a result, the size of the bubble nucleated was estimated to be 5.8–7 nm. Nanobubbles strengthen the role of the pressure booster of bubbles for improving the hydrogen storage capacity via the hydrogen clathrate hydrate (HCH). Additionally, the post-nucleation growth of nanobubbles in ice from 5.8 to 7 nm to ∼13.8 ± 3.3 μm likely connects the molecular to geological hydrogen storages. Lastly, this work is helpful to design and develop 3-D printed programmable bubble-born cryo-materials coupled to other hydrogen storage systems, e.g. the HCH.